More harm than good? The anatomy of misguided shielding of the ovaries.

OBJECTIVE: Popular gonad shield designs aim to provide coverage of the true pelvis, which is presumed to be the probable location of the ovaries. Shields are frequently placed inaccurately, especially in children, obscuring important orthopaedic landmarks on pelvic radiographs. We aimed to identify the position of the ovaries and asses how this may vary with age and the degree of bladder filling. We aimed to identify the position of the ovaries and asses how this may vary with age and the degree of bladder filling. METHODS: Using MRI examinations of the pelvis in women and children, we located 594 ovaries in 306 female patients aged from birth to 59 years. RESULTS: This study provides new evidence that bladder filling affects ovary position. A lower than expected number of patients had both ovaries within the pelvis if the bladder contained more than a moderate volume of urine. Bladder emptying should be achieved wherever practical if a shield is used. In children under the age of 7 years, more than half (19/37) had at least one ovary outside the true pelvis. There was a significant association between age and ovary position, with the percentage of patients with one or both ovaries outside the true pelvis decreasing with age (χ(2), p<0.0001). CONCLUSION: The embryological descent of the ovaries into the pelvis would appear to continue after birth, well into childhood. Current popular shield designs are therefore inappropriate for use in young children. Given the high risk of obscuring critical landmarks, coupled with the new evidence that even accurate placement will not necessarily protect the ovaries, the use of pelvic shields in girls should be reconsidered.

Anatomical variation in the position of the brachiocephalic trunk (innominate artery) with respect to the trachea: a computed tomography-based study and literature review of Innominate Artery Compression Syndrome.

Respiratory compromise due to tracheal compression by the brachiocephalic trunk (BT), a condition first labeled as Innominate Artery Compression Syndrome (IACS), has been controversially attributed to an anomalous origin of this vessel to the left of, and hence crossing, the trachea. The aim of this study was to establish the normal relationship between the BT and trachea in infants, children, and young adults without obstructive respiratory symptoms. One hundred and eighty-one computed tomography (CT) examinations of the thorax, in three age groups, were reviewed. In axial cross section, the origin of the BT from the aortic arch was identified. The BT origin, with respect to the trachea, was recorded as for a clock face, approximated to the nearest half hour. There were 62 CTs in Group 1 (1 day to 3 years of age), 48 CTs in Group 2 (10-15 years), and 71 examinations in Group 3 (20-40 years). In 96.8% of Group 1, 91.7% of Group 2, and 74.6% of Group 3 the BT origin was to the left of the trachea, between the half past twelve and 3 o'clock positions. The BT origin occurred more the left in Group 1 when compared with the other two groups (P < 0.001). An origin of the BT to the left of the trachea is a normal finding in children and young adults without obstructive respiratory symptoms. There is a tendency for the origin to become progressively more rightward with age.

The use of gonad shielding in paediatric hip and pelvis radiographs.

The problem of inaccurate placement of gonad shields in children has been highlighted by several publications nationally and internationally over the past decade and more. Here, we review the literature and present the results of a regional audit designed to assess the use and accuracy of placement of gonad shields for hip and pelvis radiographs in children. 100 consecutive anteroposterior hip or pelvis radiographs in patients under the age of 16 years were reviewed in each of 9 centres. We also included the most recent and all previously available relevant radiographs. A total of 2405 radiographs were reviewed with regard to the presence of a shield and to the accuracy of any shield placement with respect to gonad protection and visualization of orthopaedic landmarks. It is recommended that gonad shields are used in all follow-up paediatric pelvis radiographs. Our results show they were only used in 70% of such cases. When placed, only 38% of all shields were considered to be positioned accurately. For cases where shielding was indicated, an accurately placed shield was present in just 26% of radiographs. Formal written departmental guidelines for shield use were only available in two centres. We conclude that clear guidelines need to be formulated which, together with shield redesign, improved training and audit, should increase effective gonad protection for children.

Vincristine as a treatment for a large haemangioma threatening vital functions.

We report the use of vincristine to treat a large steroid resistant haemangioma of the lower face and neck. At the time of treatment the lesion had shown no signs of involution. The haemangioma was not life threatening but extension within the mouth was associated with bleeding and ulceration, which was impairing feeding and speech development. A significant improvement was seen with vincristine treatment.

Stereoacuity and foveal fusion in adults with long-standing surgical monovision.

PURPOSE: Although binocular vision deficits occur in children who have a constant esotropia onset following significant maturation of stereopsis, it is uncertain whether adults are susceptible to changes to binocular vision. We examined binocular vision in adults with longstanding surgical monovision (> or =6 month's duration) to determine whether the binocular visual system remains susceptible to change. METHODS: Participants included 32 adults with longstanding monovision through laser-assisted in situ keratectomy or photorefractive keratectomy and 20 age-matched control subjects. After full binocular correction, binocular function was measured by using the Randot Stereoacuity Test, the Randot Preschool Stereoacuity Test, and the Worth 4-dot test at near and distance. Monovision patients were grouped as having low anisometropia (<1.5 spherical D) or moderate anisometropia (> or =1.5 spherical D). RESULTS: Non-parametric analysis of variance revealed a significant difference between group median stereoacuity (H = 16.062; P <.001). Pairwise multiple comparisons indicated both groups with monovision had significantly worse stereoacuity compared with control subjects (P <.05). Median stereoacuity values were 100 seconds of arc for patients with low anisometropia, 150 seconds of arc for patients with moderate anisometropia, and 40 seconds of arc for control subjects. A larger proportion of patients with moderate anisometropia failed the Worth-4 dot test at distance than control subjects (z = 2.619; P =.009). CONCLUSIONS: Reduced stereoacuity and an absence of foveal fusion in adults with longstanding surgical monovision suggest continued susceptibility of the binocular visual system to anomalous binocular experience.

A comparison of grating visual acuity, strabismus, and reoperation outcomes among children with aphakia and pseudophakia after unilateral cataract surgery during the first six months of life.

PURPOSE: The method of correcting aphakia after unilateral cataract extraction during infancy is controversial. Some authorities advocate correction with an intraocular lens (IOL) whereas others advocate correction with a contact lens (CL). We compared grating visual acuity, alignment, and reoperative outcomes in age-matched children treated with these 2 modalities at 5 clinical centers. METHODS: Twenty-five infants born in 1997 or 1998 with a dense unilateral congenital cataract who had cataract surgery coupled with (IOL group, n = 12) or without (CL group, n = 13) primary IOL implantation were enrolled in this study. All patients were prescribed half-time occlusion therapy. In July 1999, their grating visual acuities, ocular alignments, and reoperation rates were assessed. RESULTS: The mean grating visual acuity (LogMAR) for the affected eye was 0.70 +/- 0.32 for the IOL group and 0.87 +/- 0.31 for the CL group (P =.19). The mean interocular difference in grating visual acuity was 0.26 +/- 0.30 for the IOL group and 0.50 +/- 0.28 for the CL group (P =.048). The incidence of strabismus (>10 PD) was 75% in the IOL group compared with 92% in the CL group (P =.24). The incidence of reoperations was 83% in the IOL group compared with 23% in the CL group (P =.003). CONCLUSIONS: Our preliminary data suggest that correcting aphakia after unilateral congenital cataract surgery with primary IOL implantation results in an improved visual outcome but a higher rate of complications requiring reoperation. A randomized clinical trial, the Infant Aphakia Treatment Study, is planned to further study the optimal treatment for aphakia following unilateral cataract extraction during infancy.

Interobserver test-retest reliability of the Randot preschool stereoacuity test.

PURPOSE: Random dot stereoacuity can be quantified to between 40 and 800 seconds of arc in preschool children by using the Randot Preschool Stereoacuity test (Stereo Optical Co, Inc, Chicago, Ill). To incorporate this test into clinic and research settings, the reliability of its stereoacuity scores obtained by separate examiners needs to be evaluated. The purpose of this study was to evaluate its interobserver test-retest reliability. METHODS: Participants included 102 consecutive children with binocular sensory function ranging from fine to no measurable stereopsis. Clinical research participants included children with anomalous binocular vision caused by strabismus, cataracts, anisometropia, and ptosis. In a prospective study, random dot stereoacuity was measured twice under masked testing conditions by 2 examiners within a 1-hour period. RESULTS: Interobserver test-retest reliability of the Randot Preschool Stereoacuity test is high among a population of children with diverse binocular sensory function. The correlation coefficient between individual test scores was highly significant (r = 0.97, P<.001). Mean differences between the 2 scores (0.021 log seconds of arc) were not significantly different from zero (t(99) = 1.33, P>.1). The upper and lower limits of agreement were narrow, reflecting both the large sample size and the small variation between the 2 test scores. Interobserver test-retest reliability of the Randot Preschool Stereoacuity test was nearly constant across levels of functional stereoacuity, patient categorization, and age at the time of the test. CONCLUSIONS: The high agreement between the Randot Preschool Stereoacuity test scores by 2 independent observers supports its use in clinical management and research settings for the quantitative assessment of binocular sensory vision, as well as in multicentered research studies.

Motion VEPs, stereopsis, and bifoveal fusion in children with strabismus.

PURPOSE: The link between nasal-temporal motion asymmetries and anomalous binocular sensory function in infantile esotropia (ET) has led to the idea that visual evoked potential responses to horizontal motion (mVE) is an alternative measure of sensory binocularity to stereopsis. A second hypothesis is that the mVEP response is a marker for bifoveal fusion. The purpose of this study was to directly evaluate these two hypotheses by examining the correspondence between the mVEP response and both stereoacuity and bifoveal fusion in a cohort of strabismic patients with variable binocular sensory function. METHODS: Motion VEPs, random dot stereopsis, and bifoveal fusion were measured in 94 children: 20 with infantile ET, 16 with infantile accommodative ET, 22 with late-onset accommodative ET, 10 with intermittent infantile strabismus, and 26 normal control participants. RESULTS: Patients with infantile ET and infantile accommodative ET had high concordance between mVEP responses and stereoacuity and mVEP responses and bifoveal fusion. Asymmetric mVEP responses were highly concordant with both no measurable stereopsis and an absence of fusional vergence. Patients with late-onset accommodative ET and intermittent infantile strabismus revealed discordance between the mVEP response and stereoacuity and high concordance between the mVEP response and bifoveal fusion. Asymmetric mVEP responses were highly concordant with the absence of bifoveal fusion and the minimum-size prism to elicit fusional vergence. CONCLUSIONS: The qualitative and quantitative relationship between the mVEP response and fusional vergence suggests that the mVEP response is an objective measure of bifoveal fusion. The availability of such a test will facilitate studies of normal development of bifoveal fusion and development of monofixation syndrome in strabismus.

Pavlovian conditioning of psychomotor stimulant-induced behaviours: has convenience led us astray?

In order to classically condition the behavioural effects of psychomotor stimulants within a test context, rats were treated for 10 days with (+)-amphetamine (1.5mg/kg), (+)-4-propyl-9-hydroxynaphthoxazine (PHNO, 30µg/kg) or vehicle prior to a 1h placement into a test box. Conditioned behavioural effects were then measured in the previously drug-paired context after a vehicle injection (drug-free test day). Each rat was videotaped for the 1h test box exposure on days 1, 4, 7 and 10 of the drug conditioning trials, and on the drug-free test day. Eleven of 28 behaviours that were scored for frequency, duration and mean bout duration (bout length) were significantly influenced by at least one of the two drugs. Amphetamine predominantly increased bout lengths while PHNO predominantly increased bout frequency. Only two measures that were influenced by the drugs exhibited clear increases over controls in a manner consistent with a classical conditioning interpretation. Behavioural sensitization clearly occurred to some of the effects of amphetamine and PHNO, but these were not the same effects as those increased on the non-drug day testing for classical conditioning. Most behavioural effects of amphetamine and PHNO are not classically conditioned, and behavioural sensitization to these drugs, while perhaps context-specific, is not due to classical conditioning. Automated measures of behaviours have provided misleading evidence concerning the similarity among behavioural effects of stimulants, sensitization and effects of exposure to an environment previously paired with stimulants. Analysis of transitions between behaviours does not support the view that stimulants increase switching or response competition, or that behavioural reorganization is responsible for sensitization. Rather, it is suggested that stimulants selectively facilitate current stimulus-guided behaviours.